CN106893030A - A kind of compound salt tolerant water-absorbing resin and preparation method thereof - Google Patents
A kind of compound salt tolerant water-absorbing resin and preparation method thereof Download PDFInfo
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- CN106893030A CN106893030A CN201510952574.3A CN201510952574A CN106893030A CN 106893030 A CN106893030 A CN 106893030A CN 201510952574 A CN201510952574 A CN 201510952574A CN 106893030 A CN106893030 A CN 106893030A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/52—Amides or imides
- C08F220/54—Amides, e.g. N,N-dimethylacrylamide or N-isopropylacrylamide
- C08F220/56—Acrylamide; Methacrylamide
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/04—Acids; Metal salts or ammonium salts thereof
- C08F220/06—Acrylic acid; Methacrylic acid; Metal salts or ammonium salts thereof
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- Chemical Kinetics & Catalysis (AREA)
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- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Polymerisation Methods In General (AREA)
Abstract
Compound salt tolerant water-absorbing resin and preparation method thereof, is formed by five kinds of raw materials through copolymerization, and the first raw material is acrylamide or acrylic acid（Sodium）；Second raw material is cationic monomer；3rd class is the one kind in vinylacetate, hydroxyethyl methacrylate；4th class is how unsaturated key function monomer；5th raw material is inorganic filler.Water-absorbing resin of the present invention is in neutral substantially, and price is less expensive, and intensity is higher and with excellent salt resistant character, can directly be applied in agricultural user.The present invention triggers polymerization using redox system, it is ensured that reaction is carried out at a lower temperature.
Description
Technical field
It is a kind of compound salt tolerant water-absorbing resin and preparation method thereof specifically the invention belongs to macromolecule material preparation area.
Background technology
High hydroscopic resin can absorb the water that suitable own wt hundreds of is to thousands of times, also has the function of keeping moisture after water suction, and moisture can discharge and be utilized under certain condition.To the high hydroscopic resin added in soil less than 0.2wt%, soil can be made to keep enough moisture to be supplied to the growth of plant in longer time, the bud ratio of seed and the survival rate of nursery stock are improved, therefore application is obtained in desert afforestation, agriculture many fields such as water conservation and planting tree；In medicine and hygiene fieldses, as absorbing material, it is widely applied in the products such as baby' diaper, sanitary napkin；In building and oilfield, quickly absorbed water the characteristic expanded using high hydroscopic resin, it can also be used to the purposes such as anti-seep water, water plugging and profile controlling.
Conventional water-absorbing resin mainly has following 3 class at present：（1）The copolymerization of acrylic acid and acrylamide or homogeneously polymerized resin；（2）Acrylic acid and starch or the graft copolymerization system of cellulose；（3）Acrylic acid or acrylamide and inorganic filler such as bentonite, such as copolymerization system of organic plant fiber such as stalk, CN1122051C, CN102633945.The absorption speed of the first two system is fast, and water absorbing capacity is strong, relatively costly, the field such as main application and health care, is unsuitable for being applied to greening, the agriculture heavy dose such as water conservation and Water in Water Shutoff in Oil Field profile control occasion.3rd individuality ties up to reduces cost, increases the aspects such as water-absorbing body intensity with preferable effect, therefore causes larger concern.
It is raw material to be mentioned using acrylamide and bentonite in Chinese patent 89101086.6, crosslinking agent is added to form water absorbent gel, the gel greatly improved solid concentration, reduce cost of material, there is more preferable anti-salt property compared to pure polymer resin simultaneously, make it that there is stronger competitiveness in agriculture, woods industry.The system meta-alkalescence, is conducive to controlling in the course of the polymerization process the viscosity of reaction system, it is to avoid polymerization control is difficult caused by bentonitic serious aquation thickening, but the alkalescence of hydrogel causes its root system to plant to have injury, defines that it uses scope.Therefore polymerization is carried out under close to neutrallty condition to prepare such water absorbent gel and just seem important, but to prepare such plural gel under neutral or solutions of weak acidity, Chinese patent CN1122051C, CN1122052C emphasize to need to add larger amount of potassium chloride to suppress bentonitic aquation thickening and ion exchange, are just conducive to the control of polymerisation.Although the addition of potassium chloride can solve the problem that the problem of plural gel meta-alkalescence, its price also costly, is unfavorable for the control of cost.Another side aspect, water-absorbing resin because stratum water contains a certain amount of salt, therefore is also required when agricultural industry is applied to its salt tolerance.Common resin water absorbent rate in the case of salt solution is significantly reduced, as Chinese patent CN102633945B introduces the water-absorbing resin that acrylic acid, acrylamide, bentonite and wheat stalk are combined preparation, Water absorption is up to 200 times in clear water, but only 24 times or so of Water absorption in 0.9%NaCl solution.
On the other hand, when composite water absorbent resin is prepared, general reaction temperature is slightly higher.As polymerization temperature reaches 55-70 DEG C in Chinese patent CN101215360A, Chinese patent CN102633945B reaches 50 DEG C, Chinese patent 89101086.6 is 50-75 DEG C, temperature higher causes that energy consumption is higher, viscosity control simultaneously for system is unfavorable, easily cause implode, cause product quality low.Therefore suitable reaction temperature and speed are controlled, is also resin-made for successful necessary condition.
The content of the invention
An object of the present invention there are provided a kind of compound salt tolerant water-absorbing resin.
The second object of the present invention there are provided the preparation method of this compound salt tolerant water-absorbing resin.
Compound salt tolerant water-absorbing resin of the present invention, it is formed by following five classes material copolymerization：First raw material is selected from one kind or its mixture in acrylamide, acrylic acid, PAA；Second raw material is selected from the one kind in acryloxyethyldimethyl benzyl ammonium chloride, methylacryloxyethyldimethyl benzyl ammonium chloride, MethacryloyloxyethylTrimethyl Trimethyl Ammonium Chloride, dimethyl diallyl ammonium chloride；3rd raw material is selected from the one kind in vinylacetate, hydroxyethyl methacrylate；4th raw material is the one kind in dimethyl diallyl ammonium chloride, N,N methylene bis acrylamide；5th raw material is inorganic filler, selected from the one kind in bentonite, kaolin；
Wherein, the mass ratio of five Type of Collective raw materials is as follows：First raw material：40-85%；Second raw material：1-20%；3rd raw material：1-10%；4th raw material：0.01-1%；5th raw material：10-30%.
When compound salt tolerant water-absorbing resin is prepared, five class raw materials provide not same-action respectively, and such as the first raw material is PAA or acrylamide, can promote the water swelling of material to provide water-absorbing-retaining performance；Second raw material is cationic monomer, space steric effect by after combined polymerization, increased polymer, has reached the purpose for improving salt tolerance, cationic monomer can suppress bentonite water swelling and ion exchange in the solution simultaneously, it is to avoid bentonite aquation causes the problem that system viscosity increases sharply；3rd class is the one kind in vinylacetate, hydroxyethyl methacrylate, this kind of monomer can provide hydroxyl or the direct binding ability that hydroxyl, reinforced resin and soil are provided by hydroxyethyl methacrylate by vinyl acetate ester hydrolysis, it is ensured that water-absorbing resin can play one's part to the full in the earth formation；4th class is how unsaturated key function monomer, sealing agent is formed chemical crosslinking, there is provided the effect of the intensity of material and holding sealing agent shape after water suction；5th raw material is inorganic filler, plays a part of reduction system cost, reinforced resin intensity, meanwhile, the inorganic filler of selection also has certain water-absorbing-retaining ability.
A kind of preparation method of compound salt tolerant water-absorbing resin, comprises the steps：
（1）Second raw material is configured to the aqueous solution, the 5th raw material is added after stirring and dissolving, be well mixed, sequentially add the first raw material, the 3rd raw material and the 4th raw material, continued stirring and form suspension so that the mass concentration of the aqueous solution of raw material is 20%-45%；
（2）At 0-10 DEG C of suspension temperature, to the first initiator is added in raw material mixed liquor, continue to remove oxygen to nitrogen is passed through in the aqueous solution, kept for -60 minutes 30 minutes；
（3）Under the conditions of nitrogen atmosphere and 0-10 DEG C, the second initiator is slowly added dropwise, 20-40 DEG C is warming up to after completion of dropping, the raw material is carried out polymerization 1-6 hours；
（4）After reaction gained jelly is through granulation, 30-80 DEG C of drying 24 hours is placed in vacuum drying chamber, granular water-absorbent resin is obtained after crushing.
In preparation process, the initiator for using is oxidation-reduction trigger system, wherein the first initiator is oxidant, for ammonium persulfate, potassium peroxydisulfate, sodium peroxydisulfate one kind, second initiator is reducing agent, is one kind of sodium sulfite, sodium hydrogensulfite, and oxidant is 1 with reducing agent mass ratio:1, initiator quality accounts for the 0.01%-0.5% of raw material gross mass.By controlling the rate of addition of the second initiator and the reaction speed of controlling reaction temperature system, it is to avoid implode.
Specific embodiment
Below by embodiment, the present invention is further illustrated, and its purpose is only that the scope for being better understood from the protection that is not intended to limit the present invention of the invention.
Embodiment 1
The second raw material propylene acyloxyethyl dimethyl benzyl ammonium chloride 11.20g is added in 500mL four-hole bottles, the 200g that adds water dissolves, continuously add bentonite 16.79g, it is subsequently adding the first raw material propylene acid amides 22.40g, 3rd raw material vinylacetate 5.60g, 4th raw material N, N- methylene-bisacrylamide 0.0056g, mechanical agitation make it be uniformly dispersed；Ice-water bath is cooled to 2 DEG C, adds sodium peroxydisulfate 0.0056g, while take sodium hydrogensulfite 0.0056g being placed in dropping funel, the 24.0g that adds water is completely dissolved it；To inert nitrogen gas are passed through in suspension, start after being kept for 60 minutes to solution of sodium bisulfite is added dropwise in suspension；Be warming up to after completion of dropping at 20 DEG C, stirring reaction is after 6 hours, discharging, cutting become it is broken after be placed in vacuum drying chamber 40 DEG C of dryings 24 hours, crush to obtain compound salt tolerant water-absorbing resin.
Embodiment 2
The second raw material dimethyl diallyl ammonium chloride 0.84g is added in 500mL four-hole bottles, the 180g that adds water dissolves, continuously add bentonite 19.32g, it is subsequently adding the first raw material propylene acid amides 58.80g, 3rd raw material hydroxyethyl methacrylate 4.20g, 4th raw material N, N- methylene-bisacrylamide 0.84g, mechanical agitation make it be uniformly dispersed；Ice-water bath is cooled to 2 DEG C, adds ammonium persulfate 0.42g, while take sodium sulfite 0.42g being placed in dropping funel, the 16.0g that adds water is completely dissolved it；To inert nitrogen gas are passed through in suspension, start after being kept for 60 minutes to sodium sulfite solution is added dropwise in suspension；Be warming up to after completion of dropping at 40 DEG C, 4h after stirring reaction hour, discharging, cutting become it is broken after be placed in vacuum drying chamber 80 DEG C of dryings 24 hours, crush to obtain compound salt tolerant water-absorbing resin.
Embodiment 3
The second raw material MethacryloyloxyethylTrimethyl Trimethyl Ammonium Chloride 1.26g is added in 500mL four-hole bottles, the 140g that adds water dissolves, continuously add bentonite 12.6g, it is subsequently adding the first raw material propylene acid sodium 107.1g, 3rd raw material hydroxyethyl methacrylate 3.78g, 4th raw material N, N- methylene-bisacrylamide 1.26g, mechanical agitation make it be uniformly dispersed；Ice-water bath is cooled to 2 DEG C, adds ammonium persulfate 0.063g, while take sodium sulfite 0.063g being placed in dropping funel, the 14.0g that adds water is completely dissolved it；To inert nitrogen gas are passed through in suspension, start after being kept for 60 minutes to sodium sulfite solution is added dropwise in suspension；Be warming up to after completion of dropping at 30 DEG C, 4h after stirring reaction hour, discharging, cutting become it is broken after be placed in vacuum drying chamber 60 DEG C of dryings 24 hours, crush to obtain compound salt tolerant water-absorbing resin.
Embodiment 4
Determine the sample of preparation water swelling speed and water absorbing capacity in distilled water.
Water-swelling property assay method：The compound salt tolerant water-absorbing resin sample 1.00g of 8-16 mesh graininess is taken, is added at room temperature in 300mL distilled water, 40 mesh sieves are crossed after 20min, 40min, 60min, 120min and 240min, remove flowable moisture, weigh the quality m of sample after water suction1, water-absorbent expanding multiple Q is calculated according to below equation：
Q=(m1-1)/1
Test result table 1.
The compound salt tolerant water-absorbing resin water-swelling property of table 1
Embodiment 5
Determine the sample of preparation water swelling speed and water absorbing capacity in salt solution.
Water-swelling property assay method：Take the compound salt tolerant water-absorbing resin sample 1.00g of 8-16 mesh graininess, it is added at room temperature in the NaCl solution of 300mL concentration 0.9%, 40 mesh sieves are crossed after 20min, 40min, 60min, 120min and 240min, flowable moisture is removed, the quality m of sample after water suction is weighed2, water-absorbent expanding multiple Q is calculated according to below equation：
Q=(m2-1)/1
Test result table 2.
The compound salt tolerant water-absorbing resin water-swelling property of table 2
Claims (4)
1. a kind of compound salt tolerant water-absorbing resin, it is characterised in that formed through copolymerization by following five kinds of raw materials；
First raw material is selected from one kind or its mixture in acrylamide, acrylic acid, PAA；
Second raw material is selected from the one kind in acryloxyethyldimethyl benzyl ammonium chloride, methylacryloxyethyldimethyl benzyl ammonium chloride, MethacryloyloxyethylTrimethyl Trimethyl Ammonium Chloride, dimethyl diallyl ammonium chloride；
3rd raw material is selected from the one kind in vinylacetate, hydroxyethyl methacrylate；
4th raw material is the one kind in dimethyl diallyl ammonium chloride, N,N methylene bis acrylamide；
5th raw material is inorganic filler, selected from the one kind in bentonite, kaolin；
Wherein, the mass ratio of five Type of Collective raw materials is as follows：First raw material：40-85%；Second raw material：1-20%；3rd raw material：1-10%；4th raw material：0.01-1%；5th raw material：10-30%.
2. a kind of preparation method for preparing compound salt tolerant water-absorbing resin as claimed in claim 1, comprises the steps：
（1）Second raw material is configured to the aqueous solution, the 5th raw material is added after stirring and dissolving, be well mixed, sequentially add the first raw material, the 3rd raw material and the 4th raw material, continued stirring and form suspension so that the mass concentration of the aqueous solution of raw material is 20%-45%；
（2）At 0-10 DEG C of suspension temperature, to the first initiator is added in raw material mixed liquor, continue to remove oxygen to nitrogen is passed through in the aqueous solution, kept for -60 minutes 30 minutes；
（3）Under the conditions of nitrogen atmosphere and 0-10 DEG C, the second initiator is slowly added dropwise, 20-40 DEG C is warming up to after completion of dropping, the raw material is carried out polymerization 1-6 hours；
（4）After reaction gained jelly is through granulation, 30-80 DEG C of drying 24 hours is placed in vacuum drying chamber, granular water-absorbent resin is obtained after crushing.
3. as claimed in claim 2 compound salt tolerant water-absorbing resin preparation method, it is characterized in that the initiator is oxidation-reduction trigger system, wherein the first initiator is oxidant, for ammonium persulfate, potassium peroxydisulfate, sodium peroxydisulfate one kind, second initiator is reducing agent, it is sodium sulfite, one kind of sodium hydrogensulfite, oxidant is 1 with reducing agent mass ratio:1.
4. as claimed in claim 2 compound salt tolerant water-absorbing resin preparation method, it is characterised in that the initiator quality accounts for the 0.01%-0.5% of raw material gross mass.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108753110A (en) * | 2018-06-26 | 2018-11-06 | 阜南县柳祥工艺品有限公司 | A kind of preparation method for the paint vehicle promoting wicker plaiting article product corrosion resistant ability |
| CN116283027A (en) * | 2023-02-03 | 2023-06-23 | 北京市政建设集团有限责任公司 | Engineering soil water reducing agent with high water content, preparation method and application thereof |
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| CN101195674A (en) * | 2006-12-06 | 2008-06-11 | 新疆大学 | Method for producing starch based amphiprotic absorbent resin with semi-interpenetrating network configuration |
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| CN104387530A (en) * | 2014-11-21 | 2015-03-04 | 天津科技大学 | Preparation method of high-content calcium bentonite water shutoff agent |
| CN105061961A (en) * | 2015-08-26 | 2015-11-18 | 北京理工大学 | Salt tolerance super water-absorbent resin |
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Patent Citations (6)
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| CN1539853A (en) * | 2003-11-01 | 2004-10-27 | 山东省科源石油化工生产力促进中心 | Method for producing high absorptive resin |
| CN101195674A (en) * | 2006-12-06 | 2008-06-11 | 新疆大学 | Method for producing starch based amphiprotic absorbent resin with semi-interpenetrating network configuration |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108753110A (en) * | 2018-06-26 | 2018-11-06 | 阜南县柳祥工艺品有限公司 | A kind of preparation method for the paint vehicle promoting wicker plaiting article product corrosion resistant ability |
| CN116283027A (en) * | 2023-02-03 | 2023-06-23 | 北京市政建设集团有限责任公司 | Engineering soil water reducing agent with high water content, preparation method and application thereof |
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Application publication date: 20170627 |